Recently, laminated films are developed as multilayered (composite) sheets capable of being used in members suitable for outdoor use such as a barrier member, a roof member, a solar cell panel member, a window member, an outdoor wooden floor member, an illumination protective member, a car member, a signboard and an adhesive label.
Such a laminated film is often produced by bonding a metal foil formed of aluminum or copper, a metal plate such as a copper plate or a metallized film to a resin film formed of a polypropylene resin, a polychlorinated vinyl resin, a polyester resin, a fluoro resin, an acryl resin or the like with an adhesive agent composition (adhesive agent), in order to improve weather resistance and the like thereof.
Further, as the adhesive agent composition to be used for the laminated film, an epoxy-based adhesive agent composition or an urethane-based adhesive agent composition is well known.
For example, Patent document 1 discloses a polyester resin capable of imparting an excellent initial cohesion force and bonding force and the like, and an urethane-based resin adhesive agent composition obtained by using such a polyester resin.
Patent document 2 discloses a polyurethane-based adhesive agent composition exhibiting superior hot water resistance when sterilizing a retort-packed food.
Patent document 3 discloses that a polyurethane-based adhesive agent composition having hydrolysis resistance is used in a solar cell back surface sealing sheet.
Further, Patent document 4 discloses a solar cell back surface sealing sheet having a bonding improvement layer formed of a polyester resin or a polyester polyurethane resin.
Furthermore, Patent document 5 discloses a polyurethane-based adhesive agent composition suitable for outdoor use and capable of exhibiting good moist-heat resistance.